[sdiy] Vactrol filters?

[scottnoanh at peoplepc.com]

I've put together a couple of Vactrol phase shifters, a 291, an LPG, and the
Korg PS3XXX Resonator (triple res filter).

Hmmm....synchronicity?

I started a Vactrol based filter summer before last, got sidetracked, tore
it down and forgot about it.  Recently I was reminded of it, so Sunday I put
it back on the breadboard.

It's turning out to be quite interesting - it's often quite unlike any other
Vactrol filter I've played with yet.  I've dubbed it the Mutant, mainly
because it's a mutated variation of the LPG structure, with a touch of
MS-20. Sallen-Key, 24/12 dB variations of LP, BP (12 dB only) and HP, plus
some unusual res/filter combos, sprinkled with a liberal dash of borrowed
Rene Schmitz circuitry, without which none of my own Vactrol designs would
exist =0).

The filter can be fairly sublime, kick out the Buchla twang, or be a bit
more in-your-face than other Vactrol filters I've come to know and love.
Well, except for the 291, sometimes that filter gets more than in your
face....

I'll post schematics after I've tested it thoroughly and am fairly sure it
won't explode.

I've started a page about the filter and  uploaded samples here:

http://mypeoplepc.com/members/scottnoanh/birthofasynth/id17.html


If nothing else, check out the third sample down - it gives one an idea
where this thing is headed.  Or not.

Cheers,
Scott